He said the campaign would seek to turn the tables on the Democrats, using the legal discovery process to try to pry documents from the DNC including any related to a dossier detailing allegations of links between Trump and Russian Federation.
The civil complaint filed in federal court in Manhattan by the Democratic National Committee alleges that Russian Federation informed Trump's campaign that it had conducted a cyber attack on the DNC, leading to the release of information damaging to Trump's rival Hillary Clinton.
Instead it knits numerous threads that have emerged in public over the past two years to paint a picture of an alleged conspiracy between the Trump campaign, the Kremlin and WikiLeaks founder Julian Assange.
No surprise that Trump turned to Twitter: "Just heard the Campaign was sued by the Obstructionist Democrats".
In a statement, DNC Chairman Tom Perez told The Post that "Russia launched an all-out assault on our democracy, and it found a willing and active partner in Donald Trump's campaign". "This constituted an act of unprecedented treachery".
"They successfully hacked the Democratic Party in 2016 and they will be back".
Russian President Vladimir Putin has also denied his nation had any role in the hacking or meddling in the 2016 election.
Friday on CNN, anchor Brooke Baldwin asked network analyst Gloria Borger react to the Democratic National Committee's lawsuit against the Trump's 2016 presidential campaign and the seriousness of it. The suit does not name Trump as a defendant, but a number of his aides are.
The lawsuit startled Republicans in Washington, D.C., and Democratic leaders, who were only briefed at the last minute about the DNC's plans to pursue civil litigation.
According to experts, the president's adversaries are seeking to create new opportunities for legal jeopardy for Trump and his associates by filing a lawsuit.
Since then, the current Russian investigation has indicted several past and current associates of the president over their links to Russia, though Trump still dismisses the probe as nothing more than a "witch hunt".
The DNC also names as a defendant the Russian military-intelligence service, the GRU, which has been accused by the USA government of orchestrating the hacks, as well as WikiLeaks, which published emails stolen from the DNC, and the group's founder, Julian Assange.
Foreign governments are generally immune from USA prosecution, but the DNC claims this suit falls into one of the exemptions to that law, since the hack amounted to the Russian government trespassing on the committee's private property.
Mr Trump's former campaign manager Paul Manafort and former foreign policy advisor George Papadopoulos - both listed in Friday's lawsuit - face charges included money laundering, conspiracy and making false statements to the FBI as part of Mr Mueller's investigation.